Silicon based sol-gel coatings have received considerable research because of their advantages in chemical and thermal stability coupled with their ability to be processed as low viscosity liquids. Sol-gel processes have been combined with organic compounds such as surfactants or block copolymers, which act as sacrificial templates in the formation of porous inorganic materials when the organic materials are selectively removed by thermal or chemical means. To change the microstructure of the sol-gel based coatings, typically a different formulation containing either different amounts of the organic template or an altogether different organic additive is required.
Some known polymer coatings can respond to stimuli such as moisture or pH. Such materials may be useful for providing a mechanical response to a change in the environment for diverse applications, including sensors and active coatings. Although various methods of depositing sol-gel coatings are known, and various methods of producing stimuli-responsive microstructured polymer films are known, there remains a need in the art for cost-effective methods of creating silicon-based coatings. Additionally, there is need for methods and materials that allow the microstructure of such silicon-based coatings to be controlled by exposure to at least one stimulus. Moreover, there is need for coatings having a fine pore structure, wherein preparation of such coatings can be achieved without additives such as surfactants and block copolymers.